4.6. Production of biocellulose by immobilized G. xylinus cells
The aim of the present part of work was to study the influence of immobilization on the production of extracellular biocellulose by G. xylinus. The optimized medium used throughout this expermint was composed of (g/l): reducing sugar, 30; yeast extract, 7; peptone, 7; dibasic sodium phosphate, 7.2; citric acid, 0.2, pH 6.5, under static condition within incubation period of 15 days.
4.6.1. Effect of entrapping cells with different gel materials on the production of extracellular biocellulose
Different gel materials …show more content…
Production of biocellulose and sugar consumption by G. xylinus entrapped on different gel materials
4.6.2. Effect of adsorption of G. xylinus cells on the production of biocellulose
This experiment deals with the study of biocellulose produced by G. xylinus cells adsorbed on different solid porous supports. The cells were adsorbed on synthetic sponge cubes (SSC), luffa pulp (LP), Pumice particles (PP), clay particles (CP), ceramics particles (CP).
An optimized culture medium containing the porous supports (about 10 particle/30 ml medium) was inoculated with one ml of bacterial culture. After 15 days incubation under static condition at 30°C. The biocelluose production and sugar consumption were determined.
The results graphically illustrated in Fig 4.11 revealed that adsorption of G. xylinus cells on luffa pulp (LP) and ceramics particles (CP) gave the highest biocellulose production and sugar consumption (14.5 g/l and 10.0 g/l, respectively) which represents increasing of 1.14- fold and 1.05 - fold, respectively from gained from free cells. On the other hand, other solid supports gave lower biocellulose …show more content…
xylinus. Data represented in Fig 4.14 exhibited the surface view for biocellulose under 15000 × magnification nanofiberils which can’t be observed due to converge by a thick layers so it has well interconnected pore network structure and biocellulose dried sheet under 10000× magnification, the biocellulose was fibrous with irregular size and shape (Fig 4.15). Observation of biocellulose under 10000 × magnification showed the fine cellulose ribbons, sometimes called fibrils. Observation of biocellulose fibril network produced by G. xylinus is shown in Fig